Update on Wild Rice Sulfate Study

Posted at: 03/14/2014 4:51 PM
Updated at: 03/14/2014 10:07 PM

A 1973 law protects wild rice waters in Minnesota. It limits the amount of something called sulfates, to 10 mg/L, in water where wild rice grows.

The state commissioned a two-year study to find out if that standard needed to be updated.

Results were just released, and the Minnesota Pollution Control Agency said that it appears sulfates themselves aren't hurting the growth of wild rice. But if they convert to sulfides, then it can be a problem.

Mining industry stakeholders and community leaders heard an update from two engineers on Friday at Mesabi Range College.

One of them, Robin Richards, is part of the Wild Rice Standards Study Advisory Committee, said her analysis of the results shows that the 10 standard is too low.

"Also, because of the geology in the region, there's a higher iron content in the water. And iron basically neutralizes any hazardous effects from the sulfate/sulfide conversion," she added.

Mike Hansel is a senior chemical engineer and VP of Barr Engineering. He explained to us that the EPA and U.S. Department of Health has picked 250 as the standard level for sulfates in drinking water. "And that's based on aesthetics and odor, not on health reasons," he said.

Hansel explained that the Minnesota Chamber is going to recommend to the MPCA that there's no need for a sulfate standard, based on the study results. And if there is a standard, it should be much higher, for example, 1600.

The MPCA told them that there are 150 facilities that monitor for sulfate levels. The agency also said that 144 of those facilities have a higher than 10 level.

Mining leaders are concerned about the standard, and want to make sure the science is verified. 

The Iron Mining Association released a statement on Friday.

"As required by Minnesota's 2011 sulfate-wild rice law, the MPCA must now engage in rulemaking to revise the sulfate standard based on this newly available science, develop criteria for identifying wild rice waters, designate water to which the standard applies, and establish the seasons in which the new standard is to be in force.  

Until this entire process is complete, the MPCA should not require businesses or municipalities to meet a 10 mg/L sulfate standard that does not provide any benefit to wild rice.  While mining operations are directly affected by this standard, the MPCA is currently monitoring sulfate discharge at 150 non-mining facilities and public data shows that nearly all of these facilities would fail to comply with the current unsupported sulfate/wild rice standard. "

Cities and communities who rely on waste water treatment systems are also concerned, since many of those cannot meet the 10 standard.

"I managed a waste water treatment facility for 33 years, and we always had issues with sulfates. We learned today that it could cost $130 per household if we have to build a reverse osmosis plant to treat the water further," said Chris Vreeland, a Hoyt Lakes city councilor.

The MPCA said they are having a peer review done of the study, and more analysis is needed.